本研究針對釤鈷磁鐵進行資源化研究，並且規劃有效的處理流程。由於釤鈷磁鐵在製造過程中因為切割、研磨、拋光等因素而產生廢料，這些廢料普遍含有釤約30-40%、鈷約50-60%以及少量的其他金屬，透過將釤鈷磁鐵廢料以浸漬、溶媒萃取等濕法冶金方式分離出釤、鈷、銅、鐵，將提供獲取戰略性資源的機會，同時也能降低廢棄物對環境的污染達到資源再利用以及永續發展之目標。本研究主軸分為浸漬溶出、金屬離子分離與純化、金屬化合物的產出之三大部分。
第一部分為釤鈷磁鐵成分組成與浸漬溶出之研究，藉由對釤鈷磁鐵進行化學成分分析並探討各項浸漬溶出之實驗參數，透過選擇性浸漬能夠達到將銅分離的效果得到最佳化浸漬。
第二部分為金屬離子分離與純化之研究，以溶媒萃取技術將浸漬液中金屬離子進行分離達到提高純度之目的。溶媒萃取流程中使用TBP進行第一階段的萃取分離，將鐵離子萃取至有機相並且釤、鈷離子保留於萃餘液中，再利用去離子水作為反萃取劑，使鐵離子藉由反萃取流程返回水相中。釤、鈷離子則是利用經由皂化反應改質的Na-D2EHPA進行第二階段萃取分離，將釤離子萃取至有機相並且鈷離子保留至萃餘液中，再利用鹽酸作為反萃取劑，將釤離子反萃取回水相。
第三部分為金屬化合物的產出之研究，透過添加草酸水溶液以及氫氧化鈉水溶液作為沉澱劑，使得分別存在於不同水溶液中的釤、鈷、鐵離子發生沉澱，最後將沉澱物利用煆燒熱處理得到氧化釤、氧化鈷、氧化鐵之產物，經過檢測其純度分別為99.58%、99.52%、98.99%。

This research provides valuable metal separation and recovery processes for samarium-cobalt magnet waste. Hydrochloric acid is used and the acid concentration, liquid-to-solid ratio, temperature and reaction time are adjusted. Selective leaching is carried out under optimal parameter conditions to obtain rich samarium, cobalt and Iron leachate, Then use solvent extraction to separate the metals. First TBP is used as the extractant to separate iron ions from the leachate, the modified Na-D2EHPA extractant separate samarium from the leachate of the remaining samarium and cobalt ions. The iron and samarium ions in the above organic phase are returned to the water phase through a stripping step using deionized water and 1M hydrochloric acid, respectively. Finally the metal ions in each aqueous solution are precipitated from the aqueous solution by adding a precipitant, and the precipitate is calcination to obtain the metal oxide. The crystal structure is analyzed and purity is checked by XRD and AAS, which confirms that the product is High purity Sm2O3, Co3O4 and Fe2O3 with economic value.

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